Spring looping machine



y 31, 1966 A. H. HAMMERSMITH 3,253,622

SPRING LOOPING MACHINE Filed April 23, 1964 films/us H. HAMMEPSM/THINVENTOR.

AT TOM/EV United States Patent 3,253,622 SPRING LOOPlNG MACHINE AloysiusH. Hammer-smith, San Francisco, Calif., assignor to Friden, Inc, acorporation of Delaware Filed Apr. 23, 1964, Ser. No. 362,030 6 Claims.(Cl. 140-103) This invention relates to an automatic spring loopingmachine, and particularly to a mechanism for trimming the connectingloops formed on the ends of precoiled springs.

The primary object of the present invention is to provide a trimming, orcutolf, device for trimming the terminal, or connecting, loops formed inthe ends of precoiled'springs, whereby the loop is cut off or trimmedshort of the body of the spring instead of penetrating into the coil ofthe spring.

Another object of the present invention is to provide automatic trimmingmeans for use in the spring looping machines shown and described in thepatents of Ashley- Ving, No. 3,040,784, issued June 26, 1962, or thepatent of Lehtonen, No. 3,156,269, issued Nov. 10, 1964. Such loopingmachines normally form a loop of substantially the full terminal coil ofthe spring which, when completely formed, normally penetrates into theinterior of the spring coil, as seen in FIG. 6 of the drawing. Suchsprings are more difiicult to aflix to their respective spring seatsthan if the coil were terminated just short of the end of the spring, asshown in FIG. 7. The present invention relates to a device comprising amodified form of anvil and the forming plate of the pick assembly,whereby the spring loop is trimmed to avoid penetration of the coil ofthe spring.

These and other objects of the present invention will be apparent fromthe description and claims which follow, and they, inturn, will be morereadily understood by reference to the accompanying drawing in which:

FIG. 1 is a plan view showing a forming turret, and the co-operatingforming tool assembly, both of which are substantially the same as thesame elements in the patent of Ashley-Wing, No. 3,040,784, or the patentof Lehtonen, No. 3,156,269, previously mentioned, as modified by mypresent invention.

FIG. 2 is a side view of the mechanism shown in FIG. 1 with the formingtool in its operative, or spring looping, position.

FIG. 3 is a partial and cross-sectional view of the mechanism shown inFIG. 2, but with the bending plate and probe, or pick, shown in FIG. 2,removed.

FIG. 4 is a detail showing the construction of the forming anvil, andthe bending and cutting plates which are mounted on the forming toolassembly, with the pick and supporting arm removed for the sake ofclarification.

FIG. 5 is a plan view of the mechanism shown in FIG. 3, showing the tipof the probe in cross-section.

FIG. 6 is an elevation of the end of a spring formed in the conventionalautomatic spring loopers, such as those shown by Ashley-Wing andLehtonen, in which the end of the terminal loop penetrates into thespace within the coil of the spring.

FIG. 7 is a similar elevation of the end of a spring showing the loopformed by the device of my present invention, and indicating the cuttingplate in phantom lines.

The spring looping machines to which the present invention is preferablyapplied, are adequately described in the patents of Ashley-Wing andLehtonen, above-mentioned. As a matter of fact, FIG. 2 of the presentapplication corresponds to FIGS. 7 and 11 in the Ashley- Wing patent,No. 3,040,784, and to FIG. 3 of the Lehtonen Patent No. 3,156,269.Obviously, only one turret and forming tool is shown in thisapplication, whereas both operating turrets and their forming tools areshown 7 3,253,622 Patented May 31, 1966 in the patents mentioned. Itwill be understood, of course, that the present invention could beapplied to either or both of the forming turrets of both of the saidpatents. It is, therefore, believed unnecessary to describe the completemachine, for reference can be made to either of the mentioned patentsfor all detailed construction other than those specifically mentionedherein.

The forming turret 64 (FIGS. 1 and 2) is pivotally mounted on asupporting plate 52, as described in those patents. A single precoiledspring 67 is delivered from a supply conduit 51 to a tube, or conduit,66 mounted in the turret by some suitable means, such as clamp 63.During its passage through the tube 66, a spring 67 is rapidly rotated,or spun, by means of vibration in the Ashley-Wing machine, or by meansof an air jet in the Lehtonen machinein the embodiment shown in thosepatents and in the present application, the spring being given aclockwise rotation as viewed from the rear or right side in FIGS. 1 and2.

An anvil member 69 is rigidly mounted on the forming turret 64 by anysuitable means, such as screws 70. This anvil is formed with a centralrecess 71 (see FIG. 4), which is aligned with the axis of the tube 66.This construction forms a pair of forming shoulders 72 and 73, which arespaced apart, but both of which lie opposed to a major portion of therespective semicircular portion of the tube 66, as shown particularly inFIGS. 1 and 5. The two shoulders are spaced from the periphery of theturret 64 and the end of the bore of the tube 66 by a secondary pair ofspacing shoulders 74 and 75 (FIGS. 1 and 5).

In the Ashley-Wing and Lehtonen spring looping machines, the spacingshoulder 75 (FIGS. l, 3 and 5) has a width of slightly greater than thewire diameter from which the spring is formed, whereby one complete turnof the spring will extend beyond the bore of the tube 66. The shoulder74 is approximately half that width, so that the spinning spring 67 willhave a shoulder formed on the inner side of the shoulder 72 againstWhich the spring abuts. This construction, as shown and described in thepatents above-mentioned, enables the spring to extend beyond the bore ofthe tube 66 one full turn and the cut end of the spring 67 to abutagainstan inner face on anvil forming shoulder 72, thus stopping thespring in the proper position for looping.

Co-operating with the turret 64 is a forming tool 186 (FIGS. 1 and 2).This tool comprises an arm 187 which is rigidly mounted on a rotatableshaft 189 (FIG. 2). The shaft is journalled in the supporting plate 52and a suitable bearing bracket 191 afiixed thereto by any suit ablemeans, such as screws 192. Enclosed within a slot formed in the free endof arm 187 and aligned with the axis of the bore of tube 66 is a formingprobe, or pick, 193, which is securedtherein by any suitable means, suchas screws 194- (FIG. 2). The lower, or outer, end of each probe forms aloop forming nose, best shown in FIG. 2, the outer edge of which isconvex and the inner edge is concave, as described in the patentsabove-mentioned. The arm 187, adjacent the lower end of pick 193, isangled, or cut away, to form anvil faces 195 (FIGS. 2 and 3) whichco-operate with the top of anvils 72 and 73 to form a perpendicular loopin the end coil of the spring 67. Associated with the probe is a singleforming plate which, in the patents mentioned, is mounted on the outerface of the nose and extends laterally over and slightly beyond theadjacent sides of the arm 187.

In the machine of the abovementioned patents the spring 67 is spun as itpasses down the bore of the tube 66, so that the cut end abuts againstthe inner surface of the shoulder 72. .At this point in a machine cyclethe forming tool 186 is rocked, whereupon the nose of probe 193 entersbetween the first and second coils of the spring and forces the. endcoil away from the balance of the spring. Immediately thereafter, theforming plate (198 in the patents mentioned) passes behind this firstcoil to hold it against the face of the anvil, and particularly theshoulders 72 and 73 thereof. Further rocking of the arm 187 causes thelower anvil faces 195 thereof to engage the end coil and bend it overthe top of the anvil shoulders 72 and 73, as shown in FIG. 2.

In the present invention the single forming plate (198 of the patentsmentioned) is replaced by two members:

A single bending plate 199, which is mounted on the end of arm 187, andso mounted that it passes the shoulder 72 by a distance sufficient topermit the terminal coil of a spring 67 to lie between it and the faceof the shoulder 72; and a cutting bar 200, which is set into the arm sothat it engages the inner face of the shoulder 73 as the forming toolmoves to its operating position. The bending, or holding, plate 199 isrounded slightly at its lower end to avoid deforming the spring (asshown in FIG. 2),

while the cutting plate 200 is formed with a shearing edge (as shown inFIG. 3).

Likewise in the instant invention, the anvil 69 is modified toco-operate with the two plates. The shoulder 72 is rounded (as shown at205 in FIG. 4), while the shoulder 73 is formed with a sharp shearingedge 206 (as shown in FIGS. 3, 4 and which is adapted to co-ope'ratewith the cutting plate 200 to form a pair of shearing jaws. The holdingplate 19? and the rounded anvil 72 are located on the side of the probeaway from the terminal end of the spring wire, i.e., on the left-handside of the probe 193 for a right-hand spring when looking from behindthe spring (from the right in FIG. 1); and the cutting plate 200 and thesharply edged shoulder 73 are placed on the outer side of the probe 193adjacent to the terminal end of the spring loop.

It is seen in FIG. 6 that the terminal end of the spring formed on themachines of the patents above-mentioned, is apt to penetrate the spacewithin the coil of the spring. This makes it rather difiicult for anoperator to apply the loop over some of its seats, especially if theseat is an aperture in some other part. In contrast to this, a springloop formed on the machine of the present invention is terminated ashort distance from the balance of the spring, as shown in FIG. 7, whichforms a loop which is readily attached to its seat.

It is obvious that the amount of loop retained, or the exact position atwhich the cutting edge 200 will trim the terminal loop, is a matter ofchoice and can be adjusted by a mechanic by changing its position on thearm 187 and adjusting the cutting anvil 73 accordingly. Obviously, thefarther the cutting plate 200 is from the axis of the shaft 189, thelonger will be the loop, and the more the plate 200 is inset into thearm 187, the shorter will be the terminal loop.

I claim:

1. In an automatic spring looping machine having:

(1) a forming anvil,

(2) means for positioning a spring against said anvil,

(3) and a forming tool operative to form a terminal loop in a springheld against the anvil, the combination which comprises:

(4) a rounded edge formed on one side of the anvil,

(5) a shearing edge formed on the other side of the anvil,

(6) a nonshearing forming plate mounted on the forr ing tool andco-operating with the rounded edge of the anvil, and

(7) a shearing plate likewise mounted on the forming tool andco-operating with the shearing edge of the anvil.

2. In an automatic spring looping machine having:

(1) a bifurcated forming anvil,

(2) means for positioning a spring against the face of said anvil,

(3) and a forming tool operative to form a terminal loop in the springheld against the face of said anvil,

the combination which comprises:

(4) a rounded edge formed on one bifurcation of said anvil,

(5) a rounded forming plate mounted on the forming tool and uponoperation of said forming tool cooperating with the rounded edge of theanvil to hold the terminal coil against the face of said anvil,

(6) a shearing edge formed on the other bifurcation of said anvil, and

(7) a shearing plate likewise mounted on the forming tool and uponoperation of said forming tool engaging the shearing edge of the anvil.

3. In an automatic spring looping machine having:

(1) a bifurcated forming anvil,

(2) means for positioning a spring against the face of said anvil,

(3) and a forming tool operative to form a terminal loop in a springheld against a face of said anvil, said forming tool including a probeadapted to penetrate the bifurcation of said anvil and to pry apredetermined number of coils of a spring held against the anvil fromthe balance of the spring,

the combination which comp-rises:

(4) a rounded shoulder formed on one bifurcation of said anvil,

(5) a shearing edge formed on the other bifurcation of said anvil,

(6) a forming plate mounted on the forming tool adjacent the probe ont'he side of said anvil with the rounded shoulder and spaced away fromthe face of said anvil upon operation of said forming tool by a distanceequivalent to the diameter of the wire of a spring, and

(7) a shearing plate mounted on the forming tool adjacent the probe onthe other side of the probe and spaced to engage the shearing edge ofthe anvil upon operation of said forming tool.

4. In an automatic spring looping machine having:

( 1) a tube for delivering a coiled spring,

. (2) means for rotating a spring during its passage through said tube,

(3) a forming anvil Which, when the tube and anvil are in operativeposition, has a transverse shoulder substantially across the diameter ofthe spring in said tube and a slot substantially perpendicular to saidshoulder, the shoulder on one side of said slot being closer to the endof the tube than the other,

(4) a forming tool having a probe adapted to penetrate said slot toseparate the terminal coil away from the balance of the spring,

(5) and means co-operating with said anvil to bend said separated coilperpendicularly and thereby form a terminal loop in the spring heldagainst the anvil,

the combination which comprises:

(6) a rounded edge formed on the side of the anvil closestto the tube,

(7) a lshearing edge formed on the other side of the anvl (8) a formingplate mounted on the forming tool adjacent the probe on the side of theforming tool cooperating with the rounded edge of the anvil and spacedaway from'the face of the anvil upon operation of the forming tool by adistance equivalent to the diameter of the wire of a spring, and

(9) a shearing plate mounted on the forming tool adjacent the probe onthe side of the forming tool co operating with the shearing edge of theanvil and spaced to engage the face of said anvil upon opera- 7 to theend of said tube.

6. In an automatic spring looping machine having:

(1) a tube for delivering a coiled spring,

(2) means for rotating a spring during its passage through said tube,

(3) a forming anvil having a transverse shoulder adapted to engage theend of the terminal coil of said spring,

(4) a forming tool having a probe adapted to separate the terminal coilaway from the balance of the spring,

(5) and means co-operating with said anvil to bend said separated coilperpendicularly and thereby form a terminal loop in the spring held bythe anvil,

means for forming the terminal loop with the end thereof spaced awayfrom the other coils of the spring which comprises the combination of:

(6) a rounded edge formed on the edge of the anvil spaced away from theface of the anvil upon operation of the forming tool by a distanceequivalent to the diameter of the Wire of a spring,

(9) a shearing plate mounted on the forming tool adjacent the probe onthe side of the forming tool cooperating with the shearing edge of theanvil and spaced to engage the face of said anvil upon operation of saidforming tool, and

(10) means for adjusting the position of the shearing plate and theanvil with respect to the end of the tube and thereby adjusting thepoint on the terminal loop at Which it is sheared.

References Cited by the Examiner UNITED STATES PATENTS 2,365,876 12/1944Hicks 140-103 2,951,512 9/1960 Wynkoop 140-103 3,156,269 11/1964Lehtonen 140-103 CHARLES W. LANHAM, Primary Examiner.

L. A. LARSON, Assistant Examiner.

1. IN AN AUTOMATIC SPRING LOOPING MACHINE HAVING: (1) A FORMING ANVIL,(2) MEANS FOR POSITIONING A SPRING AGAINST SAID ANVIL, (3) AND A FORMINGTOOL OPERATIVE TO FORM A TERMINAL LOOP IN SPRING HELD AGAINT THE ANVIL,THE COMBINATION WHICH COMPRISES: (4) A ROUNDED EDGE FORMED ON ONE SIDEOF THE ANVIL, (5) A SHEARING EDGE FORMED ON THE OTHER SIDE OF THE ANVIL,(6) A NONSHEARING FORMING PLATE MOUNTED ON THE FORMING TOOL ANDCO-OPERATING WITH THE ROUNDED EDGE OF THE ANVIL, AND (7) A SHEARINGPLATE LIKEWISE MOUNTED ON THE FORMING TOOL AND CO-OPERATING WITH THESHEARING EDGE OF THE ANVIL.